The present disclosure relates to a switching circuit and a RF (Radio Frequency) switch including the same.
In accordance with the development of wireless communications technology, various communications standards have been used simultaneously. In addition, in accordance with the miniaturization of wireless communications modules and improvements in the performance of portable communications terminals, the need for single portable communications terminals to conform to a plurality of communications standards has become apparent. Therefore, the amount of frequency bands that a single portable communications terminal cellular phone should support has increased.
That is, in many cellular communications reception areas, existing second-generation (2G) and third-generation (3G) communications technologies have been supplemented with new communications technologies, such that fourth-generation (4G) communications schemes such as Long Term Evolution (LTE) have been widely implemented. In addition, in Wi-Fi areas, the IEEE 802.11ac standard has been added to the existing IEEE 802.11b/g/n to enhance marketability thereof.
In accordance with this trend, there has also been demand for support for various frequency bands within a radio frequency (RF) front end field. For example, there has been demand for support of various frequency bands with respect to a RF switch positioned on a signal path between an antenna and an RF chipset. Therefore, a Single Pole Double Throw (SPDT) type switch has been used in various fields.
Meanwhile, a Metal Oxide Silicon Field Effect Transistor (MOSFET), an example of a switching device used in a RF switch may be a floating body type transistor or a body contact type transistor. Such a floating body type transistor has excellent insertion loss, but harmonic performance thereof may be deteriorated. On the contrary, the body contact type transistor has excellent harmonic performance, but insertion loss performance thereof may be deteriorated.
The following Related Art Document (Patent Document 1), which relates to a switching circuit apparatus, discloses that a leakage current suppressing circuit unit is provided to an output unit of a driver circuit to suppress the intrusion of high frequency signals. However, unlike the present disclosure, contents in which a body terminal is not floated and a positive voltage is applied to a body of a switching device when the switching device is turned on to thereby significantly reduce a voltage difference between the body and a source of the switching device, are not disclosed in Patent Document 1.